In a gas turbine using natural gas as fuel, multiple connecting pipes connect a natural gas supply device to a combustion chamber of the gas turbine, wherein natural gas burns after being mixed with oxygen-containing gas from a compressor, thereby driving the operation of the gas turbine. The composition of natural gas may vary with its source and place of production, but the main constituent thereof is alkanes, especially methane. If the natural gas used contains a high level of constituents other than methane, condensates will form in the gas supply device and connecting pipes after a certain period of operation. These condensates consist mainly of propane, butane, pentane, ethylene, propylene and acetylene, etc., and are waxy, flammable and corrosive. If measures are not taken, the condensates which steadily build up may even enter the combustion chamber, affecting the combustion chamber nozzles as well as the stability of combustion.
Existing gas turbines are equipped with drainage systems for collecting condensed water from the natural gas supply device and connecting pipes when the turbines are shut down. Such drainage systems can only operate when the natural gas supply device has ceased operation (i.e. there is no natural gas in the connecting pipes), and so are only suitable for natural gas containing a low level of components other than methane. Since the flowability of the condensates is poor, such drainage systems are also unable to be used for the collection of condensates produced by natural gas containing a high level of components other than methane. Thus the question of how to increase the adaptability of a gas turbine to natural gas with different constituents, so that the gas turbine is suitable for natural gas containing a high level of constituents other than methane, is a question which urgently awaits solution in the art.